DB_BLOCK_SIZE is the SGA initialization parameter that is used to determine the size of database blocks in bytes.

Oracle recommends that your database block size match, or be multiples of your operating system block size. One can use smaller block sizes, but the performance cost is significant. The choice should depend on the type of application you are running. If you have many small transactions as with OLTP, use a smaller block size. With fewer but larger transactions, as with a Data warehousing (DW) application, use a larger block size.

Monday, January 17, 2011

Character sets are how we store data,A Character set is specified when creating a database, and your choice of character set determines what languages can be represented in the database. This choice also influences how you create the database schema and develop applications that process character data. It also influences interoperability with operating system resources and database performance.